Method and apparatus for transmitting HARQ-ACK in wireless communication system

1. A method for transmitting a Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) in a wireless communication system, the method comprising: determining Physical Uplink Control Channel (PUCCH) resources for a plurality of downlink subframes, using an HARQ-ACK Resource Offset (ARO); and transmitting HARQ-ACKs through the PUCCH resources in one uplink (UL) subframe, wherein both an enhanced Interference Mitigation and Traffic Adaptation (eIMTA) user equipment (UE) and a non-eIMTA UE are configured to transmit HARQ-ACK for downlink (DL) subframes of a first subframe set, by using the one UL subframe, wherein only the eIMTA UE is configured to transmit HARQ-ACK for DL subframes of a second subframe set, by using the one UL subframe, wherein the ARO consists of a first value related to a PUCCH resource shift for the DL subframes of the first subframe set, when the plurality of downlink subframes consist of the DL subframes of the first subframe set, and wherein the ARO consists of both the first value and a second value related to a PUCCH resource shift for the DL subframes of the second subframe set, when the plurality of downlink subframes consist of the DL subframes of the first subframe set and the DL subframes of the second subframe set.

2. The method according to claim 1 , wherein PUCCH resources for the first subframe set and PUCCH resources for the second subframe set are contiguous.

3. The method according to claim 1 , wherein the PUCCH resources are determined using a lowest of indexes of Enhanced Control Channel Elements (ECCEs) in an Enhanced Physical Downlink Control Channel (EPDCCH).

4. A User Equipment (UE) for transmitting a Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) in a wireless communication system, the UE comprising: a reception device; and a processor, wherein the processor is configured to determine Physical Uplink Control Channel (PUCCH) resources for a plurality of downlink subframes, using an HARQ-ACK Resource Offset (ARO), and transmit HARQ-ACKs through the PUCCH resources in one uplink (UL) subframe, wherein both an enhanced Interference Mitigation and Traffic Adaptation (eIMTA) UE and a non-eIMTA UE are configured to transmit HARQ-ACK for downlink (DL) subframes of a first subframe set, by using the one UL subframe, wherein only the eIMTA UE is configured to transmit HARQ-ACK for DL subframes of a second subframe set, by using the one UL subframe, wherein the ARO consists of a first value related to a PUCCH resource shift for the DL subframes of the first subframe set, when the plurality of downlink subframes consist of the DL subframes of the first subframe set, and wherein the ARO consists of both the first value and a second value related to a PUCCH resource shift for the DL subframes of the second subframe set, when the plurality of downlink subframes consist of the DL subframes of the first subframe set and the DL subframes of the second subframe set.

5. The UE according to claim 4 , wherein PUCCH resources for the first subframe set and PUCCH resources for the second subframe set are contiguous.

6. The UE according to claim 4 , wherein the PUCCH resources are determined using a lowest of indexes of Enhanced Control Channel Elements (ECCEs) in an Enhanced Physical Downlink Control Channel (EPDCCH).